Does 'Local' have another purpose?

I was wondering why the following code snippet gives an error if the Local keyword is omitted:

Local StringArray:String[] = ["Here's","a","string"]

Print StringArray[2].length
Print SizeOf(StringArray) 

I thought Local was for declaring a variable inside a function or method to be non-global and is released when the function returns. What does that have to do with the example above?

Is Local required for some other reason(s), too?

Thanks,
Russell